Submission #656907

#	Time	Username	Problem	Language	Result	Execution time	Memory
656907		Melika0gh	Travelling Merchant (APIO17_merchant)	C++17	100 / 100	140 ms	4052 KiB

merchant

#include<bits/stdc++.h>
using namespace std;

typedef long long int ll;

const ll inf = 1121272678990188431;
const int maxn = 1e2+10, maxk = 1e3+10;
ll b[maxn][maxk], s[maxn][maxk], dis[maxn][maxn], new_w[maxn][maxn], max_ben[maxn][maxn];
int n, m, k;

void FloydWarshall(ll d[maxn][maxn])
{
	for(int w = 0; w < n; w++)
		for(int v = 0; v < n; v++)
			for(int u = 0; u < n; u++)
				d[v][u] = min(d[v][u], d[v][w] + d[w][u]);
	
	return;
}

void CalcBen()
{
	for(int v = 0; v < n; v++)
		for(int u = 0; u < n; u++)
			for(int l = 0; l < k; l++)
				if(b[v][l] != -1 && s[u][l] != -1)
					max_ben[v][u] = max(max_ben[v][u], s[u][l] - b[v][l]);
	
	return;
}

bool Valid(ll x)
{
	for(int v = 0; v < n; v++)
	{
		for(int u = 0; u < n; u++)
		{
			if(dis[v][u] == inf)
				new_w[v][u] = inf;
			else
				new_w[v][u] = x * dis[v][u] - max_ben[v][u];
		}
	}
	
	FloydWarshall(new_w);
	for(int v = 0; v < n; v++)
		if(new_w[v][v] <= 0)
			return true;
	
	return false;
}

ll Bs(ll l, ll r)
{
	if((r - l) <= 1)
		return l;
	
	ll mid = (l + r) / 2;
	if(Valid(mid))
		return Bs(mid, r);
	else
		return Bs(l, mid);
}

int main()
{
	cin >> n >> m >> k;
	for(int i = 0; i < n; i++)
		for(int j = 0; j < k; j++)
			cin >> b[i][j] >> s[i][j];
	
	for(int i = 0; i < n; i++)
		fill(dis[i], dis[i] + n, inf);
	
	for(int i = 0; i < m; i++)
	{
		int v, u;
		ll w;
		cin >> v >> u >> w;
		v--, u--;
		dis[v][u] = w;
	}
	
	FloydWarshall(dis);
	CalcBen();
	
	ll ans = Bs(0, 1e9+10);
	cout << ans << '\n';
}

• Subtask 1: 12 / 12
• Subtask 2: 21 / 21
• Subtask 3: 33 / 33
• Subtask 4: 34 / 34